as far as i know... the SAS hba are supported and used... so that you can create a LUN and map to esxi via RDM...so it is possible...i dont think it will be a issue..
I would like to hear from any one else in community.. who has tested.. with this kind of setup for microsoft cluster.. when i checked in the DELL articles.. the SAS HBA are used...for the DAS storage and we can create and map LUNS to esxi...